Rust常用数据结构教程 序列

news/2024/11/13 8:51:51/

文章目录

  • 一、Vec
    • 1.Vec与堆栈
    • 2.什么时候需要Vec
    • 3.get()方法
    • 4.与枚举的结合
  • 二、VecDeque
    • 1.什么情况适合VecDeque
    • 2.VecDeque的方法
  • 三、LinkedList
    • 1.什么时候用LinkedList
  • 参考

一、Vec

可变数组(vector)数组存储在heap上,在运行时(runtime)可以增加或减少数组

长度

  • 有人把Vector翻译为矢量
  • 注意默认还是不可变

1.Vec与堆栈

Vec的buf是存储在heap上的，其他存储在栈上

rust">pub struct Vec<T, #[unstable(feature = "allocator_api'", issue = "32838")] A:Alocator=Global>
{
buf: RawVec<T, A>,
len: usize, //长度
}pub(crate) struct RawVec<T, A: Allocator = Global> {
ptr: Unique<T>, // 指向
cap: usize, // capacity
alloc: A,
}

2.什么时候需要Vec

·首选Vec:当你不知道用什么的时候，试试Vec，性能强悍有保证
·当你想要一个长度实时变化的数据存储单元时
·当你希望自己的存储单元有序时
·当你希望内存中各个元素的存储地址是连续时

rust">#[derive(Debug, Clone)]
struct Car {id: i32,name: String,
}fn main() {// 初始化方法let my_vec = vec![2, 3, 4];println!("{:#?}: {}", my_vec, my_vec.capacity());// /这里的语法表示创建一个长度为 3 的向量，并用 2 填充每个元素let my_vec = vec![2; 3];println!("{:#?}: {}", my_vec, my_vec.capacity());// 可以显示声明类型，也可以不显示声明类型let my_vec: Vec<i32> = Vec::new();println!("{:#?}: {}", my_vec, my_vec.capacity());let my_vec: Vec<i32> = Vec::with_capacity(5);println!("{:#?}: {}", my_vec, my_vec.capacity());// pushlet mut cars = Vec::new();for i in 1..11 {let car_type = if i % 2 == 0 { "car" } else { "bus" };cars.push(Car {id: i,name: format!("{}-{}", car_type, i),});}println!("{:?}", cars);//删除poplet car = cars.pop().unwrap();println!("{:?}", cars);println!("{:?}", car);//删除：固定index删除let car = cars.remove(0);println!("{:?}", cars);println!("{:?}", car);//队尾插入：pushcars.push(car.clone());println!("{:?}", cars);// 队首插入：insertcars.insert(0, car.clone());println!("{:?}", cars);// get set// 不推荐cars[9] = Car {id: 11,name: "car-11".to_string(),};println!("{:?}", cars);// 推荐let item = cars.get(0);println!("{:?}", item);let item = cars.get_mut(9).unwrap();*item = Car {id: 10,name: "car-10".to_owned(),};println!("{:?}", cars);let mut cars2 = vec![car.clone(), car.clone()];cars.append(&mut cars2);println!("{:?}", cars);println!("{:?}", cars2);let car_slice = cars.as_slice();println!("{:?}", car_slice);// 清理cars.clear();println!("{:?}", cars);println!("{:?}", cars.is_empty());
}

编译及运行

 cargo runCompiling data_struct v0.1.0 (/home/wangji/installer/rust/data_struct/data_struct)
warning: fields `id` and `name` are never read--> src/main.rs:3:5|
2 | struct Car {|        --- fields in this struct
3 |     id: i32,|     ^^
4 |     name: String,|     ^^^^|= note: `Car` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis= note: `#[warn(dead_code)]` on by defaultwarning: `data_struct` (bin "data_struct") generated 1 warningFinished `dev` profile [unoptimized + debuginfo] target(s) in 5.81sRunning `target/debug/data_struct`
[2,3,4,
]: 3
[2,2,2,
]: 3
[]: 0
[]: 5
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 10, name: "car-10" }]
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }]
Car { id: 10, name: "car-10" }
[Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }]
Car { id: 1, name: "bus-1" }
[Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 1, name: "bus-1" }]
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 1, name: "bus-1" }]
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 11, name: "car-11" }]
Some(Car { id: 1, name: "bus-1" })
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 10, name: "car-10" }]
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 10, name: "car-10" }, Car { id: 1, name: "bus-1" }, Car { id: 1, name: "bus-1" }]
[]
[Car { id: 1, name: "bus-1" }, Car { id: 2, name: "car-2" }, Car { id: 3, name: "bus-3" }, Car { id: 4, name: "car-4" }, Car { id: 5, name: "bus-5" }, Car { id: 6, name: "car-6" }, Car { id: 7, name: "bus-7" }, Car { id: 8, name: "car-8" }, Car { id: 9, name: "bus-9" }, Car { id: 10, name: "car-10" }, Car { id: 1, name: "bus-1" }, Car { id: 1, name: "bus-1" }]
[]
true

3.get()方法

rust">
#![allow(unused)]
fn main() {
let v = vec![1, 2, 3, 4, 5];let third: &i32 = &v[2];
println!("The third element is {}", third);match v.get(2) {Some(third) => println!("The third element is {}", third),None => println!("There is no third element."),
}
}
~/installer/rust/bobo/abc master 
 cargo runCompiling abc v0.1.0 (/home/wangji/installer/rust/bobo/abc)Finished `dev` profile [unoptimized + debuginfo] target(s) in 7.48sRunning `target/debug/abc`
The third element is 3
The third element is 3
~/installer/rust/bobo/abc master 


4.与枚举的结合

rust">
#![allow(unused)]
fn main() {enum SpreadsheetCell {Int(i32),Float(f64),Text(String),}let row = vec![SpreadsheetCell::Int(3),SpreadsheetCell::Text(String::from("blue")),SpreadsheetCell::Float(10.12),];match &row[1] {SpreadsheetCell::Int(i) => println!("Found an int: {}", i),_ => println!("No int found"),}
}

编译及运行

 cargo runCompiling abc v0.1.0 (/home/wangji/installer/rust/bobo/abc)Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.29sRunning `target/debug/abc`
No int found

二、VecDeque

一个双向的动态数组

与Vec 类似，与Vec 不同的是,它对容器的两端进行 移除和插入

VecDeque的两端插入、删除都是O（1）级别的

VecDeque并一定是连续的

1.什么情况适合VecDeque

有双端插入和删除需求的

双向需求queue

2.VecDeque的方法

继承了Vec的所有方法

自身的方法

rust">push_back\push_front (取代了push)
pop_frontlpop_back(取代了pop)
contains
frontifront_mut
back\back_mut

Example：

rust">use std::collections::VecDeque;
#[derive(Debug, Clone)]
struct Car {id: i32,name: String,
}fn main() {let mut int_queue: VecDeque<i32> = VecDeque::new();println!("{:?} cap {}", int_queue, int_queue.capacity());int_queue.push_back(3);println!("{:?} cap {}", int_queue, int_queue.capacity());let mut int_queue: VecDeque<i32> = VecDeque::with_capacity(20);println!("{:?} cap {}", int_queue, int_queue.capacity());let mut cars = VecDeque::from([Car {id: 1,name: String::from("Car-1"),},Car {id: 2,name: String::from("Car-2"),},Car {id: 3,name: String::from("Car-3"),},]);println!("{:?} cap {}", cars, cars.capacity());// VecDeque// pushcars.push_back(Car {id: 4,name: "Car-4".to_string(),});println!("{:?} cap {}", cars, cars.capacity());cars.push_front(Car {id: 0,name: "Car-0".to_string(),});println!("{:?} cap {}", cars, cars.capacity());// poplet back_car = cars.pop_back();println!("{:?}", back_car);println!("{:?} cap {}", cars, cars.capacity());let front_car = cars.pop_front();println!("{:?} ", front_car);println!("{:?} cap {}", cars, cars.capacity());// front// backprintln!("{:?}", cars.front());println!("{:?}", cars.back());// getprintln!("car{:?}", cars[1]); //不安全操作let car = cars.get(1).unwrap(); //安全操作println!("car{:?}", car);let car = cars.get_mut(1).unwrap();*car = Car {id: 10,name: "Car-n".to_owned(),};println!("car{:?}", cars);cars.clear();println!("{:?}", cars.is_empty());
}

编译及运行

 cargo runBlocking waiting for file lock on build directoryCompiling data_struct v0.1.0 (/home/wangji/installer/rust/data_struct/data_struct)
warning: variable does not need to be mutable--> src/main.rs:13:9|
13 |     let mut int_queue: VecDeque<i32> = VecDeque::with_capacity(20);|         ----^^^^^^^^^|         ||         help: remove this `mut`|= note: `#[warn(unused_mut)]` on by defaultwarning: fields `id` and `name` are never read--> src/main.rs:4:5|
3 | struct Car {|        --- fields in this struct
4 |     id: i32,|     ^^
5 |     name: String,|     ^^^^|= note: `Car` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis= note: `#[warn(dead_code)]` on by defaultwarning: `data_struct` (bin "data_struct") generated 2 warnings (run `cargo fix --bin "data_struct"` to apply 1 suggestion)Finished `dev` profile [unoptimized + debuginfo] target(s) in 8.30sRunning `target/debug/data_struct`
[] cap 0
[3] cap 4
[] cap 20
[Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }] cap 3
[Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }, Car { id: 4, name: "Car-4" }] cap 6
[Car { id: 0, name: "Car-0" }, Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }, Car { id: 4, name: "Car-4" }] cap 6
Some(Car { id: 4, name: "Car-4" })
[Car { id: 0, name: "Car-0" }, Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }] cap 6
Some(Car { id: 0, name: "Car-0" }) 
[Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }] cap 6
Some(Car { id: 1, name: "Car-1" })
Some(Car { id: 3, name: "Car-3" })
carCar { id: 2, name: "Car-2" }
carCar { id: 2, name: "Car-2" }
car[Car { id: 1, name: "Car-1" }, Car { id: 10, name: "Car-n" }, Car { id: 3, name: "Car-3" }]
true

三、LinkedList

通过链式存储数据的一种序列数据结构

A double-linked with owned nodes

1.什么时候用LinkedList

·根据Rust文档，LinkedList数据结构在分割/追加方面是高效的

如果您希望对分配多少内存以及何时分配内存有非常细粒度的控制，那么链表是一个不错的选择。但是绝大多数你用不到，而且你要考虑成本

rust">use std::collections::LinkedList;#[derive(Debug, Clone)]
struct Car {id: i32,name: String,
}
// vecque 方法都有
// vec 无
fn main() {let mut int_link: LinkedList<i32> = LinkedList::new();let mut cars = LinkedList::from([Car {id: 1,name: "Car-1".to_string(),},Car {id: 2,name: "Car-2".to_string(),},Car {id: 3,name: "Car-3".to_string(),},]);cars.push_back(Car {id: 4,name: "Car-4".to_string(),});println!("back: {:?}", cars.back());cars.push_front(Car {id: 0,name: "Car-0".to_string(),});println!("front: {:?}", cars.front());println!("{:?}", cars);let car = cars.pop_back().unwrap();println!("{:?}", car);let car = cars.pop_front().unwrap();println!("{:?}", car);/*** split_off 是一个方法，用于将 Vec 切成两部分。它会将 cars 向量从指定的索引位置分成两部分，并返回从该位置开始的所有元素，同时将这些元素从原向量中移除。*/let mut car_list = cars.split_off(cars.len() - 2);println!("---{:?}", car_list);println!("{:?}", cars);cars.append(&mut car_list);println!("{:?}", cars);println!("{:?}", car_list);cars.clear();println!("{}", cars.is_empty());
}

编译及运行：

 cargo runCompiling data_struct v0.1.0 (/home/wangji/installer/rust/data_struct/data_struct)
warning: unused doc comment--> src/main.rs:44:5|
44 | /     /**
45 | |      * split_off 是一个方法，用于将 Vec 切成两部分。它会将 cars 向量从指定的索引位置分成两部分，并返回从该位置开始的所有元素，同时将这些元素从原向量中移除。
46 | |      */| |_______^
47 |       let mut car_list = cars.split_off(cars.len() - 2);|       -------------------------------------------------- rustdoc does not generate documentation for statements|= help: use `/* */` for a plain comment= note: `#[warn(unused_doc_comments)]` on by defaultwarning: unused variable: `int_link`--> src/main.rs:11:13|
11 |     let mut int_link: LinkedList<i32> = LinkedList::new();|             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_int_link`|= note: `#[warn(unused_variables)]` on by defaultwarning: variable does not need to be mutable--> src/main.rs:11:9|
11 |     let mut int_link: LinkedList<i32> = LinkedList::new();|         ----^^^^^^^^|         ||         help: remove this `mut`|= note: `#[warn(unused_mut)]` on by defaultwarning: fields `id` and `name` are never read--> src/main.rs:5:5|
4 | struct Car {|        --- fields in this struct
5 |     id: i32,|     ^^
6 |     name: String,|     ^^^^|= note: `Car` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis= note: `#[warn(dead_code)]` on by defaultwarning: `data_struct` (bin "data_struct") generated 4 warnings (run `cargo fix --bin "data_struct"` to apply 1 suggestion)Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.13sRunning `target/debug/data_struct`
back: Some(Car { id: 4, name: "Car-4" })
front: Some(Car { id: 0, name: "Car-0" })
[Car { id: 0, name: "Car-0" }, Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }, Car { id: 4, name: "Car-4" }]
Car { id: 4, name: "Car-4" }
Car { id: 0, name: "Car-0" }
---[Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }]
[Car { id: 1, name: "Car-1" }]
[Car { id: 1, name: "Car-1" }, Car { id: 2, name: "Car-2" }, Car { id: 3, name: "Car-3" }]
[]
true

参考


http://www.ppmy.cn/news/1545904.html

相关文章

怎样使用pycharm中的服务？

怎样使用pycharm中的服务？

在PyCharm中使用服务&#xff0c;你需要执行以下步骤&#xff1a; 打开PyCharm&#xff0c;并在项目中创建一个新的Python文件。在Python文件中&#xff0c;编写你的代码来创建和使用服务。根据你想要使用的服务类型&#xff0c;可能需要安装相关的库或模块。在PyCharm的菜单栏…
阅读更多...
Springboot+thymeleaf结合Vue，通过thymeleaf给vue赋值解决Vue的SEO问题

Springboot+thymeleaf结合Vue，通过thymeleaf给vue赋值解决Vue的SEO问题

通过结合Spring Boot、Thymeleaf和Vue&#xff0c;可以充分利用Thymeleaf的服务端渲染功能&#xff0c;解决Vue全客户端渲染带来的SEO问题。以下是结合上述SEO优化重点的具体实现思路&#xff1a; 1. 在服务端渲染Title标签关键词 在Spring Boot控制器中定义页面的标题&#…
阅读更多...
Vue全栈开发旅游网项目(9)-用户登录/注册及主页页面开发

Vue全栈开发旅游网项目(9)-用户登录/注册及主页页面开发

1.用户登录页面开发 1.查询vant组件 2.实现组件模板部分 3.模型层准备 4.数据上传 1.1 创建版权声明组件Copyright 新建文件&#xff1a;src\components\common\Copyright.vue <template><!-- 版权声明 --><div class"copyright">copyright xx…
阅读更多...
vue+exceljs前端下载、导出xlsx文件

vue+exceljs前端下载、导出xlsx文件

首先安装插件 npm install exceljs file-saver第一种 简单导出 //页面引入 import ExcelJS from exceljs; import {saveAs} from file-saver; export default {methods: { /** 导出操作 */async handleExportFun() {let that this// 获取当前年月日 用户下载xlsx的文件名称设…
阅读更多...
无人机之飞行管控平台篇

无人机之飞行管控平台篇

无人机的飞行管控平台是一种基于互联网和物联网技术的智能管理系统&#xff0c;旨在实现对无人机飞行任务的全自动化、全过程化管理。 一、主要功能 飞行计划管理&#xff1a;用户可以通过平台提前设置好无人机的飞行计划&#xff0c;包括起飞时间、航线、飞行高度等信息。平…
阅读更多...
《EasyQuotation 与MongoDB在股市信息的奇妙融合》

《EasyQuotation 与MongoDB在股市信息的奇妙融合》

《EasyQuotation 与MongoDB在股市信息的奇妙融合》 一、EasyQuotation 的强大功能二、数据存入 MongoDB&#xff08;一&#xff09;配置与连接&#xff08;二&#xff09;存储方法 三、K 线图监视股市信息&#xff08;一&#xff09;自定义性能趋势图表&#xff08;二&#xff…
阅读更多...
亚马逊评论爬虫+数据分析

亚马逊评论爬虫+数据分析

爬取评论 做分析首先得有数据&#xff0c;数据是核心&#xff0c;而且要准确&#xff01; 1、爬虫必要步骤&#xff0c;选好框架 2、开发所需数据 3、最后测试流程 这里我所选框架是seleniumrequest&#xff0c;很多人觉得selenium慢&#xff0c;确实不快&#xff0c;仅针对此…
阅读更多...
富格林：揭露欺诈陷阱用心追损

富格林：揭露欺诈陷阱用心追损

富格林指出&#xff0c;现货黄金投资作为一种比较受青睐的投资方式&#xff0c;已经赢得了很多投资理财者的关注了。但是投资现货黄金需要对黄金相关的交易操作和技巧有深入的了解&#xff0c;才能够规避欺诈陷阱用心追损。事实上&#xff0c;掌握一定的交易技巧对于规避欺诈陷…
阅读更多...
最新文章

Copyright @ 2022~2023